This question already has an answer here:
The flux of cosmic ray muons is about 1 muon per square centimeter per minute. I was trying to see if I can detect these using a glass of water, putting it in a totally dark room and take a picture of that with a camera mounted on a tripod. I used the highest ISO setting available and exposed for about half a minute, and I let the camera perform a dark frame subtraction. Muons moving through the water should produce photons, some of which will be detected by the camera sensor.
I then converted the raw files using the dcraw program to tiff files without doing any demosaicing (so each pixel corresponds to the actual gray value detected by a sensor photosite). But I'm now a bit bogged down in analyzing the raw files (a problem here is that the Sony ARW files are not real raw files, they have build in lossy compression which is not ideal for doing this sort of analysis).
So far I have not seen any interesting, if I look at gray values that are many standard deviations above the noise then I don't see any obvious (broken) straight line patterns. So, I'm wondering if one would actually expect any signal at all. It seems to me that you would because from close up you would detect some photons from the water, but perhaps I'm too optimistic.